This invention relates to an apparatus and a method for trenching subsea pipelines. The pipelines can be constructed out of any usual material and used to transport any usual gas, liquid or slurry. In practicing the invention, a trenching sled is pulled along the pipe and a trench is left behind, after which the trailing pipeline settles in the trench.
There are many known methods for trenching subsea pipelines including water jetting and mechanical cutting methods.
Typical jet sleds cannot trench effectively in hard bottom conditions and traditional mechanical cutter machines have not been successful in sandy soils or for pre-laid rigid pipelines. Ploughs are usually designed for a single job and are only really effective for soft soils of a consistent nature such as cohesiveless sands or soft claves.